The future of the Sunrise Powerlink is shaping up as a battle between the president of the California Public Utilities Commission and one of the commissioners, with advice from the governor and leaders of the state Senate.

PUC President Michael Peevey is backing San Diego Gas & Electric's arguments that the 1,000-megawatt line is needed to ensure a reliable power supply for San Diego, and that it will foster development of electricity from renewable sources.

Commissioner Dian Grueneich is skeptical of the proposal. She says the line can't be justified unless SDG&E uses it substantially for “green” electricity, generated by the sun, wind or water heated underground. She wants to mandate conditions to make sure that happens, conditions that SDG&E finds untenable.

Yesterday, Gov. Arnold Schwarzenegger wrote a letter to the commission, urging it to side with Peevey when it takes up the issue tomorrow.

“This project is a vital link in California's renewable energy future and must be approved as soon as possible,” he wrote.

Schwarzenegger also voiced his support of the project last year.

In yesterday's letter, he conceded that the state will fail to meet its goal of getting 20 percent of its electricity from renewable sources by 2010.

Schwarzenegger spokeswoman Lisa Page said the governor has weighed in on PUC projects on issues such as energy efficiency and decreasing greenhouse gas emissions.

The head of the San Diego group the Utility Consumers'Action Network, Michael Shames, doesn't remember another time when a governor has written to the commission urging it to vote in a particular way.

Schwarzenegger's letter came just days after Senate President Pro Tem Darrell Steinberg, D-Sacramento, and three other senators wrote him saying the Peevey proposal could allow imports of energy from burning coal.

The senators, including Christine Kehoe, D-San Diego, urged him to back conditions like those that Grueneich proposed to ensure the line is used for green power.

The conditions they proposed would require SDG&E to get a third of its power from renewable sources, ban it from using Sunrise for coal power, require it to replace any contracts that fall through with new renewable power from the same region and establish performance milestones.

SDG&E has said it will voluntarily do the things Steinberg and Kehoe are asking for, but it won't submit to requirements as a condition for getting approval to build Sunrise.

Grueneich modified her initial conditions in response to SDG&E complaints, but even the new requirements, which would mandate proof that the line would be used for energy from the sun and other renewable sources, were unacceptable to the utility.

The company said it would not build the line under those conditions because it can't be sure it will pay off.

The debate over the Peevey and Grueneich proposals is an indication that the commission is likely to dismiss the recommendations of administrative law judges who said it cannot be justified economically or environmentally.